Dielectric materials

ABSTRACT

A dielectric material is provided. The material includes α[Ca 1-x-y Ba x Sr y (Ca 1-z Cu z )Cu 2-p La 2p/3 Ti 4-q M q O 12-δ ]+(1−α)[Ba r Sr 1-r TiO 3 ], wherein M is aluminum, chromium, zirconium, or combinations thereof; x can vary between the value of zero and 0.1 such that 0≦x≦0; y, z, and r can vary between the value of zero and 1 such that 0≦y≦1, 0≦z≦1, and 0≦r≦1; p and q can vary between the value of zero and 0.1 such that 0≦p≦0.1 and 0≦q≦0.1; δ can vary between the value of zero and 0.05 such that 0≦δ≦0.05; and α can vary between the value of 0.5 and 1 such that 0.5≦α≦1, with a proviso that when x=y=0 and z=α=1, p and q are greater than zero; and when x=y=z=0, p and q are not simultaneously zero. A dielectric component including the dielectric material and a system including the dielectric component are provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of co-pending U.S. patentapplication Ser. No. 12/778,189, entitled “DIELECTRIC MATERIALS FORPOWER TRANSFER SYSTEM” filed 12 May 2010, which is hereby incorporatedby reference herein in its entirety.

This application is related to co-pending U.S. patent application Ser.No. 13/075,911, entitled “DIELECTRIC MATERIALS” filed contemporaneouslyherewith, which application is hereby incorporated by reference.

BACKGROUND

The invention relates generally to dielectric materials, and, inparticular, to rare-earth-element-based titanate systems.

A dielectric material is an insulating material that does not conductelectrons easily and thus has the ability to store electrical energywhen a potential difference exists across it. Common dielectricmaterials include glass, mica, mineral oil, paper, paraffin,polystyrene, plastics, phenolics, epoxies, aramids, and porcelain. Inelectronic circuits, dielectric materials may be employed as capacitors.High dielectric constant materials may be used in radar or microwaveapplications and for circuit miniaturization as the speed of propagationof signal is related to the dielectric constant of the medium throughwhich it passes. If the loss tangent for a material of a given frequencysignal is very low, the electrical loss related to the hysteresisdecreases resulting in an efficient signal transmission.

There is a need for a dielectric material that has one or more desirablecharacteristics, such as, a high dielectric constant, a low losstangent, the ability to withstand a wide range of temperatures, theability to operate in wide range of frequencies, voltages, atmosphericconditions, and pressures, and the capability for use in the manufactureof composite structures that can be used alone or in combination withother materials.

BRIEF DESCRIPTION

Briefly, in one embodiment, a material is provided. The materialcomprises Ca_(1-x-y)Ba_(x)Sr_(y)Ti_(1-z)Cr_(z)O_(3-δ)A_(p), wherein A isnitrogen, fluorine, or combinations thereof; x and y can vary betweenthe value of zero and one such that 0<x<1 and 0<y<1; z can vary betweenthe value of zero and 0.01 such that 0≦z≦0.01; and δ and p can varybetween the value of zero and one such that 0≦δ≦1 and 0≦p≦1, with aproviso that z and p are not simultaneously zero.

In one embodiment, a dielectric component is provided. The dielectriccomponent comprises a material comprisingCa_(1-x-y)Ba_(x)Sr_(y)Ti_(1-z)Cr_(z)O_(3-δ)A_(p), wherein A is nitrogen,fluorine, or combinations thereof; x and y can vary between the value ofzero and one such that 0<x<1 and 0<y<1; z can vary between the value ofzero and 0.01 such that 0≦z≦0.01; and δ and p can vary between the valueof zero and 1 such that 0≦δ≦1 and 0≦p≦1, with a proviso that z and p arenot simultaneously zero.

In another embodiment, a system is provided. The system comprises adielectric component. The dielectric component comprises a materialcomprising Ca_(1-x-y)Ba_(x)Sr_(y)Ti_(1-z)Cr_(z)O_(3-δ)A_(p), wherein Ais nitrogen, fluorine, or combinations thereof; x and y can vary betweenthe value of zero and one such that 0<x<1 and 0<y<1; z can vary betweenthe value of zero and 0.01 such that 0≦z≦0.01; and δ and p can varybetween the value of zero and 1 such that 0≦δ≦1 and 0≦p≦1, with aproviso that z and p are not simultaneously zero.

In one embodiment, a material is provided. The material comprisesα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof; xcan vary between the value of zero and 0.1 such that 0≦x≦0; y, z, and rcan vary between the value of zero and 1 such that 0≦y≦1, 0≦z≦1, and0≦r≦1; p and q can vary between the value of zero and 0.1 such that0≦p≦0.1 and 0≦q≦0.1; δ can vary between the value of zero and 0.05 suchthat 0≦δ≦0.05; and α can vary between the value of 0.5 and 1 such that0.5≦α≦1, with a proviso that when x=y=0 and z=α=1, p and q are greaterthan zero; and when x=y=z=0, p and q are not simultaneously zero.

In one embodiment, a dielectric component is provided. The dielectriccomponent comprises a material comprisingα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof; xcan vary between the value of zero and 0.1 such that 0≦x≦0; y, z, and rcan vary between the value of zero and 1 such that 0≦y=1, 0≦z≦1, and0≦r≦1; p and q can vary between the value of zero and 0.1 such that0≦p≦0.1 and 0≦q≦0.1; δ can vary between the value of zero and 0.05 suchthat 0≦δ≦0.05; and α can vary between the value of 0.5 and 1 such that0.5≦α≦1, with a proviso that when x=y=0 and z=α=1, p and q are greaterthan zero; and when x=y=z=0, p and q are not simultaneously zero.

In another embodiment, a system is provided. The system comprises adielectric component. The dielectric component comprises a materialcomprisingα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof; xcan vary between the value of zero and 0.1 such that 0≦x≦0; y, z, and rcan vary between the value of zero and 1 such that 0≦y≦1, 0≦z≦1, and0≦r≦1; p and q can vary between the value of zero and 0.1 such that0≦p≦0.1 and 0≦q≦0.1; δ can vary between the value of zero and 0.05 suchthat 0≦δ≦0.05; and α can vary between the value of 0.5 and 1 such that0.5≦α≦1, with a proviso that when x=y=0 and z=α=1, p and q are greaterthan zero; and when x=y=z=0, p and q are not simultaneously zero.

DRAWINGS

These and other features, aspects, and advantages of the presentinvention will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 illustrates an example system including a dielectric componentemploying dielectric materials according to an embodiment of theinvention;

FIG. 2-121 illustrate dielectric properties of some of exemplarymaterials according to an embodiment of the invention.

DETAILED DESCRIPTION

Embodiments of the present invention include materials that havedifferent compositions and may be used as dielectric materials.

In the following specification and the claims that follow, the singularforms “a”, “an” and “the” include plural referents unless the contextclearly dictates otherwise.

Materials having low dielectric loss tangent along with high dielectricconstant are desired for various electrical applications. Therefore,materials that have both high dielectric constant and low dielectricloss tangent at the frequency of operation of intended applications aredesirable.

In one embodiment, it is desirable to use dielectric materials whosedielectric properties such as dielectric constant and loss tangent aresubstantially stable over a certain frequency range of the desiredapplications. The term “substantially stable” herein means that thechange in values does not lead to more than about 10% of the performancevariation of the power transfer system. Thus, the required value andwidth of the frequency ranges may vary depending on the applications forwhich the material is used. In one embodiment, the desired frequencyrange is from about 100 Hz to about 100 MHz. In some embodiments, thedesired frequency range is from about 1 kHz to about 100 kHz. In anotherembodiment, the desired frequency range is from about 100 kHz to about 1MHz. In one more embodiment, the desired frequency range is from about 1MHz to about 5 MHz.

The dielectric materials that have the desired dielectric properties canbe employed in multiple applications. Non limiting examples includevaractor diode replacement, tunable capacitors with low losses, tunablefilters, phase shifters, multiplexers, voltage control oscillators,tunable matching network for power amplifiers, low noise amplifiers,general impedance matching network.

FIG. 1 illustrates an exemplary system 10 employing dielectric materialsaccording to an embodiment of the invention. In this example, acontactless power transfer system includes a first coil 12 coupled to apower source 14 and configured to produce a magnetic field (not shown).A second coil 16 is configured to receive power from the first coil 12and distribute to a load 20. A dielectric component in the form of afield focusing element 18, including a dielectric material according toan embodiment of the present invention is disposed between the firstcoil 12 and the second coil 16 for focusing the magnetic field frompower source 14. In another embodiment, the field focusing element maybe used to focus electric fields and/or electro-magnetic fields.

Materials such as, but not limited to, barium strontium titanate andcalcium copper titanate are examples of materials exhibiting highdielectric constants. Barium strontium titanate—(Ba, Sr)TiO₃—and calciumcopper titanate—CaCu₃Ti₄O₁₂—have different crystal structures andexhibit different temperature dependent characteristics. For example,(Ba, Sr)TiO₃ belongs to a perovskite family and is a ferroelectricmaterial. CaCu₃Ti₄O₁₂ is not a ferroelectric material and has a bodycentered cubic (b.c.c) structure. The factors influencing the dielectricproperties such as dielectric constant and dielectric loss tangent inthe (Ba, Sr)TiO₃ and CaCu₃Ti₄O₁₂ systems may also be different. Forexample, it is believed that the generation and ordering of dipoles is areason for the Ferro electricity and the high dielectric constant in the(Ba, Sr)TiO₃ system, while the CaCu₃Ti₄O₁₂ system is thought to have theeffects arising from barrier layer capacitance by having insulatinggrain boundaries and semi conducting grains.

In one embodiment, the dielectric material is used as a bulk material.The term “bulk material” as used herein indicates any material that hasa three dimensional structure with all of the sides greater than about 1mm In one embodiment, the dielectric materials are used as coatings. Thecoating can be in a thin film form or in a thick film form. As usedherein a “thin film” has a thickness less than about 100 microns, whilea thick film can have thickness from about a hundred microns to about amillimeter.

In one embodiment, a combination of materials can be used for gettingdifferent desirable dielectric properties such as, for example, highdielectric constant low loss tangent values, constant dielectricconstant over a varied frequency range, and constant dielectric constantover a varied voltages. For example, a mixture of two or more materialshaving high dielectric constant or two or more materials having highpermeability can be used as a dielectric material for a particularapplication. In another example, a mixture of two or more materials,each having different desirable properties at a particular frequency orvoltage range may be used as a dielectric material.

The inventors studied different ways of improving the desirabledielectric properties of the dielectric materials belonging to the (Ba,Sr)TiO₃ and CaCu₃Ti₄O₁₂ systems. The different methods investigated forthe property enhancements include, but are not limited to, cationdoping, anion doping, grain boundary doping, density increment,composite formations, and changing the sintering conditions, sinteringatmospheres, and structural and microstructural aspects.

Accordingly, in one embodiment, a material system represented byCa_(1-x-y)Ba_(x)Sr_(y)Ti_(1-z)Cr_(z)O_(3-δ)A_(p) is provided, wherein Ais nitrogen, fluorine, or combinations thereof; 0<x<1; 0<y<1; 0≦z≦0.01;0≦δ≦1; and 0≦p≦1, with a proviso that z and p are not simultaneouslyzero. This material system will be henceforward referred to as “BSTmaterial system” for simplicity. As used herein in the BST materialsystem, the representationCa_(1-x-y)Ba_(x)Sr_(y)Ti_(1-z)Cr_(z)O_(3-δ)A_(p) is a theoreticalformula including the mixtures and compounds that are in the specifiedratio to be denoted by this formula, and does not necessarily mean thata single compound exists in a form that can be identified by standardcharacterization techniques. In short, a material specified by the aboveformula may actually exist as multiple phases which, taken collectively,has an overall composition as specified by the formula.

As used herein and elsewhere in this application, the term ‘greater thanzero’ denotes that the intended component is intentionally added, ratherthan an incidental amount that may be present as an impurity. Further,end points of the ranges include incidental variations above and belowthe stated number, as appropriate for normal measurement and processvariations.

In one embodiment, a material system with the formulaα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃]is provided, wherein M is aluminum, chromium, zirconium, or combinationsthereof, and 0≦x≦0.1, 0≦y≦1, 0≦z≦1, 0≦p≦0.1, 0≦δ≦0.05, 0≦r≦1, and0.5≦α≦1, with a proviso that when x=y=0 and z=α=1, p and q are greaterthan zero; and when x=y=z=0, p and q are not simultaneously zero. Thefirst part of this material system is is denoted herein as “CCT materialsystem”. The second part is a variation of BST material system.Therefore the material system with the representationα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃]will be henceforward referred to as “CCTBST material system” forsimplicity.

As used herein in the CCTBST material system, the representationCa_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)andα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃]are theoretical formulae including the mixtures and compounds that arein the specified ratio to be denoted by these formulae, and do notnecessarily mean that a single compound exists in a form that can beidentified by standard characterization techniques. In short, a materialspecified by the above formulae may actually exist as multiple phaseswhich, taken collectively, have an overall composition as specified bythe formulae.

In general, the cation dopants were found to increase resistance of thegrain boundary by absorbing the oxygen vacancies and thereby decreaseboth the dielectric constant and loss tangent. By doping at cation site,the doped cation gets reduced by absorbing electron density at the grainboundary, thereby decreasing conduction of the grain boundary, thusleading to the decrease in dielectric constant and loss.

In general, by doping at the anion site, the cation of the lattice getsreduced by absorbing the electron density thereby creating insulatingplanar defects in the grains. The insulating planar defects can reducethe electrical resistivity of internal barrier of the grains and therebydecrease the dielectric loss.

In the BST material system, the barium and strontium levels were variedand studied for their effects on favorable dielectric properties. Thus,in one embodiment, a BST material system is provided such that0.9≦(x+y)≦1. Therefore, in this embodiment, the calcium doping iscomparatively less as seen in the exampleBa_(0.55)Sr_(0.4)Ca_(0.05)Ti_(1-z)Cr_(z)O_(3-δ)A_(p). In a furtherembodiment, 0.3≦x and (x+y)=1. Therefore, in this embodiment the BSTmaterial system does not contain calcium or any other dopants in thebarium or strontium sites. Example of the above BST material systemincludes, but is not limited to,Ba_(0.3)Sr_(0.7)Ti_(1-z)Cr_(z)O_(3-δ)A_(p).

In one embodiment of the BST material system, the titanium is partiallyreplaced by chromium, which may help to decrease the loss tangent. Inone embodiment, the chromium is substituted for less than about 2 atomic% of titanium in the BST material system. In a subsequent embodiment,the chromium substitution is in the range of about 0.01 atomic % toabout 1 atomic %. Thus, in this embodiment, the quantity z in theformula above varies between about 0.0001 and about 0.01. In a furtherembodiment, the chromium substitution is in the range of about 0.2atomic % to about 1 atomic % of titanium with the z value varyingbetween about 0.002 and about 0.01.

In one embodiment, 0<z≦0.01 and (x+y)=1 in a BST material system.Therefore, in this embodiment, there is a certain level of chromiumsubstitution at the titanium sites. An example for this system includesBa_(0.3)Sr_(0.7)Ti_(0.99)Cr_(0.01)O_(3-δ)A_(p). In one embodiment, in aBST material system, z>0, and δ and p are both equal to 0. In thisembodiment, the BST material system comprises cation substitutions, butnot anion substitutions. Examples of the above BST material systemsinclude, but are not limited to, Ba_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃,Ba_(0.3)Sr_(0.7)Ti_(0.995)Cr_(0.005)O₃, andBa_(0.4)Sr_(0.6)Ti_(0.998)Cr_(0.002)O₃.

In a BST material system, when titanium is substituted with a trivalentcation, such as chromium in the above example, the oxygen level can alsostoichiometrically change. For instance in the systemBa_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃, the number of oxygen atoms canbe 2.999, instead of 3, to accommodate substitution of 0.002 atoms ofchromium. In one embodiment, in the BST material system, the barium orstrontium is partially replaced by calcium and titanium is partiallyreplaced by chromium. Examples of the above BST material systemsinclude, but are not limited to,Ba_(0.55)Sr_(0.4)Ca_(0.5)Cr_(0.002)Ti_(0.908)O₃.

Table 1 below represents some examples of the BST material systems andtheir dielectric properties with the varying levels of barium andstrontium and with some cation dopants.

TABLE 1 Dielectric BST material system Frequency constant Loss tangentBa_(0.4)Sr_(0.6)Cr_(0.002)Ti_(0.998)O₃ 1 kHz-1 MHz >740 <0.09 ~339kHz >740 ~0.0004 Ba_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ 1 kHz-1 MHz >910<0.009 ~660 kHz >910 <0.0002

In one embodiment of the power transfer system with a BST materialsystem, the oxygen is partially replaced through anion doping. Nitrogenand fluorine are two examples of anion dopants used to substitute foroxygen. Oxygen in the BST material system may be substituted by nitrogenand fluorine individually or in a combination. In one embodiment, oxygenis substituted by nitrogen or fluorine such that 0≦δ≦1; and 0≦p≦1 in theBST material system. Therefore, in one embodiment, the anionsubstitution is such that about 25% or less of oxygen in the BSTmaterial system is substituted by anion. In one embodiment, depending onthe process conditions, the nitrogen is in an oxidation state of −3while substituting for oxygen in the BST material system. In oneembodiment, the oxygen is substituted by an anion such that 0≦δ≦1 and0≦p≦0.8. In one embodiment, the substitution replaces less than about 10atomic % of oxygen in the BST material system. In one embodiment, theoxygen is substituted by anion such that 0<δ≦0.5 and 0<p≦0.4 and in afurther embodiment, the substitution is such that 0.1≦δ≦0.5 and0.1≦p≦0.4.

In one embodiment of the BST material system, oxygen is substituted byanother anion such that z=0, and 0.1≦δ≦0.5 and 0.1≦p≦0.4. Thus in thisembodiment, the anion substitutions are conducted in the absence oftitanium substitution. A non-limiting example for this system can berepresented by Ba_(0.3)Sr_(0.7)TiO_(2.8)N_(0.13). This material shows anextremely low dielectric loss of about 0.0001 with a suitable dielectricconstant of about 506 at the frequency of about 2.5 MHz.

In one embodiment, the oxygen is substituted by fluorine such that0<δ≦1; and 0<p≦0.4. In a further embodiment, the oxygen is substitutedby fluorine such that 0.1≦δ≦1; and 0.1≦p≦0.4. In one embodiment,depending on the process conditions, the fluorine is in an oxidationstate of −1 while substituting for oxygen in the BST material system. Inanother embodiment, the oxygen is substituted by both nitrogen andfluorine such that 0.1≦δ≦0.5 and 0.05≦p≦0.3.

In one example, the inventors incorporated fluorine into the BSTmaterial system by varying the starting materials for preparation of BSTmaterial system and noted a decrease in the loss tangent as a result. ABa_(0.4)Sr_(0.6)TiO₃ material was prepared by using BaF₂ and SrF₂ as thesource of barium and strontium respectively. By starting with thefluoride sources for barium and strontium, it is expected that some ofthe fluorine will be substituted for oxygen, thus changing thedielectric values of the BST materials system. The Ba_(0.4)Sr_(0.6)TiO₃prepared by using BaF₂ and SrF₂ showed a dielectric loss factor lessthan about 0.01 over the entire frequency range from 100 Hz to 10 MHzwith a minimum of 0.0001 at 1.4 MHz. The material also showed a uniformdielectric constant of about 415 over the entire frequency rangementioned above. The material may be advantageously used forapplications that require frequency independent operation.

In one embodiment, the BST material system is doped with both cationsand anions. Thus, in one embodiment, titanium is partially replaced bychromium and oxygen is partially replaced by anions such that z, δ and pare all greater than zero. In a further embodiment, 0<z≦0.01, 0<δ≦0.5,and 0<p≦0.4. Examples of these systems includeBa_(0.3)Sr_(0.7)Ti_(0.995)Cr_(0.005)O_(2.8)N_(0.13) andBa_(0.4)Sr_(0.6)Ti_(0.995)Cr_(0.005)O_(2.8)N_(0.13). The materialrepresented by Ba_(0.4)Sr_(0.6)Ti_(0.995)Cr_(0.005)O_(2.8)N_(0.13)demonstrates a loss tangent of about 0.003 with a dielectric constant ofabout 819 at the frequency of about 3.13 MHz. In a further embodiment,0<(x+y)<1 and z, δ, and p are all greater than zero such that calciumdopant is present in the barium or strontium site, chromium partiallysubstitutes titanium, and nitrogen and/or fluorine partially substitutesoxygen. Table 2 provides dielectric values of some of the anion-dopedmaterials in the BST material system with and without cation dopants.

TABLE 2 Die- lectric Loss BST material system Frequency constant tangentBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.13)   ~1 MHz >500 ~0.005 ~2.5 MHz >500~0.00015 Ba_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.13)   ~1MHz >480 ~0.005 ~2.7 MHz ~470 ~0.0004 F doped Ba_(0.4)Sr_(0.6)TiO₃ 100Hz-10 MHz >400 <0.01 prepared by using BaF₂ and 1.49 MHz ~400 ~0.0001SrF₂ as Ba and Sr source respectively

As presented earlier, in one embodiment, a CCTBST material system isprovided with a combination of CCT material system and BST materialsystem such thatα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof, and0≦x≦0.1, 0≦y≦1, 0≦z≦1, 0≦p≦0.1, 0≦q≦0.1, 0≦δ≦0.05, 0≦r≦1, and 0.5≦α≦1,with a proviso that when x=y=0 and z=α=1, p and q are greater than zero;and when x=y=z=0, p and q are not simultaneously zero. Thus, in oneembodiment comprising CCTBST material system to be used in thefield-focusing element 18, x and y are both equal to zero and z=1, andthe copper is partially replaced by other suitable cations such as, forexample, lanthanum. Further, the titanium is partially replaced byaluminum, chromium, zirconium, or any of their combinations. In oneembodiment, any or all of the above mentioned replacements coexist. Whenx=y=0, the CCTBST material system will not have barium and strontiumsubstitution in the calcium place. When α=1, the CCTBST material systembecomes CCT material system. When z=1, the number of copper atompresent, including lanthanum substitution, in the CCTBST material systemis about 3. Thus the proviso that of when x=y=0 and z=α=1, p and q aregreater than zero denotes a CaCu₃Ti₄O₁₂ system with substitution incopper and titanium sites. The lanthanum substitution at the copper siteof CaCu₃Ti₄O₁₂ may vary such that 0<p≦0.1. Similarly titanium can besubstituted by aluminum, chromium, zirconium, or any combination suchthat 0<q≦0.1. Depending on the valence states of titanium sitesubstitutions, the oxygen may be stoichiometric or non-stoichiometric.Therefore, in the above system δ varies such that 0≦δ≦0.05. Examplesinclude CaCu_(2.9)La_(0.067)Ti_(3.99)Zr_(0.01)O_(12-δ) andCaCu₃Ti_(3.92)Cr_(0.02)Al_(0.06)O_(12-δ). Table 3 lists some of theproperties of the substituted CaCu₃Ti₄O₁₂ material.

TABLE 3 Dielectric Loss CCT material system Frequency constant tangentCaCu_(2.9)La_(0.067)Ti_(3.94)Al_(0.06)O_(11.97) 10 kHz-60 kHz >6000 <0.1CaCu_(2.9)La_(0.067)Ti_(3.98)Cr_(0.02)O_(11.99) ~10 kHz >12000 <0.2

In one embodiment, when x=y=z=0 and α=1, the CCTBST material systemapproaches substituted Ca₂Cu₂Ti₄O₁₂. The substitution can be at thecopper site, at the titanium site or the combination of copper andtitanium substitutions. In one embodiment, Ca₂Cu₂Ti₄O₁₂ is a material inthe CCT material system of the field-focusing element 18 with about 33.3mole % of CaCu₃Ti₄O₁₂ and about 66.7 mole % of CaTiO₃. This material, inthe doped form exhibits some good dielectric properties. Examples forthe substituted Ca₂Cu₂Ti₄O₁₂ with good dielectric properties includeCa₂Cu₂Ti_(3.94)Al_(0.06)O_(12-δ) and Ca₂Cu₂Ti_(3.98)Cr_(0.02)O_(12-δ).Further examples along with their dielectric properties can be seen fromthe Table 4.

TABLE 4 Dielectric CCT material system Frequency constant Loss tangentCa₂Cu₂Ti_(3.99)Zr_(0.01)O_(11.995) 100 kHz-130 kHz >2000 <0.08Ca₂Cu₂Ti_(3.94)Al_(0.06)O_(11.97) 3.5 kHz-10 kHz  >2000 <0.04  10kHz-100 kHz >2000 <0.06 Ca₂Cu_(1.9)La_(0.067)Ti₄O₁₂ 100 kHz-130kHz >1500 <0.09

In one embodiment, in the power transfer system comprising a CCTBSTmaterial system, x>0. In a related embodiment, y>0. In one furtherembodiment, x>0 and y>0. In an exemplary embodiment, x>0 and y>0 alongwith z=α=1 and p=q=0. Thus, in the above embodiments, calcium ispartially replaced by barium and/or strontium and the CCTBST materialsystem approaches CCT material system. One example of a CCT materialsystem prepared with barium and strontium dopants and demonstrating verygood dielectric properties is Ba_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂. Thismaterial has a substantially uniform dielectric constant and losstangent values over a wide range of frequency ranges, which makes thismaterial useful for an application that will work over a variable rangeof frequencies. The dielectric constant for the materialBa_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂ lies in the range of about 4500-5000and the loss tangent is in the range of about 0.06 to 0.08 for theentire frequency range from about 1 kHz to about 100 k Hz. The materialis suitable for contactless power transmission at any frequency lying inthe range of about 1 kHz to 100 kHz. Another example for the CCTmaterials with x>0 and y>0 along with z=α=1 and p=q=0, exhibiting gooddielectric properties include Ba_(0.01)Sr_(0.1)Ca_(0.89)Cu₃Ti₄O₁₂.

The examples presented herein depict the different CCT material systemswith their approximate measured dielectric constant and loss tangentvalues. While some particular examples are presented herein, thevariations in the dopant combinations and levels will be appreciated byone skilled in the art.

In one embodiment of the CCTBST material system, when 0.5≦α<1, thedielectric material comprises (1−α)[Ba_(r)Sr_(1-r)TiO₃], along with theCCT material system. The CCTBST material of this form can be mixtures orcoexistence of the CCT and BST material systems with the above mentionedformula limitations, but some of the materials of this system were foundto be increasing favorable dielectric properties that are not predictedby rule of mixtures. One example of this dielectric material is(0.6CaCu₃Ti₄O₁₂+0.4SrTiO₃). Individually while CaCu₃Ti₄O₁₂ has adielectric value >6000 at the frequency range of about 10 kHz to about35 kHz, the loss tangent value is around 0.1. The dielectric constantand loss tangent values of SrTiO₃ at this frequency range are about 70and 0.26 respectively. However, the combination(0.6CaCu₃Ti₄O₁₂+0.4SrTiO₃) has a dielectric constant value greater thanabout 7000 and the loss tangent value less than about 0.09 at thefrequency range from about 10 kHz to about 35 kHz. Another example ofthis dielectric material is(0.6CaCu₃Ti_(3.94)Al_(0.06)O_(11.97)+0.4SrTiO₃). This combination has adielectric constant value greater than about 9000 and the loss tangentvalue less than about 0.09 at the frequency range from about 1 kHz toabout 10 kHz. One more example of this material system includes(0.6CaCu₃Ti_(3.98)Cr_(0.02)O_(12-δ)+0.4SrTiO₃).

The inventors further conducted experiments on the dielectric materialsby treating the materials in different atmospheres such as anoxygen-rich atmosphere, a nitrogen atmosphere, a chromium atmosphere, ora reducing atmosphere such as a hydrogen atmosphere, for example. Anoxygen-rich atmosphere, for example, is able to effect changes in thedielectric properties of CCT, BST, and therefore CCTBST familymaterials. It is observed that in the CCT family materials, sintering inthe oxygen atmosphere compensates the oxygen vacancies in the materials,thus leading to lower dielectric constant and lower loss tangent. In theBST material system, sintering in the oxygen atmosphere increases thedensity of materials and thus increases the dielectric constant.Sintering in nitrogen atmosphere is expected to take out some of theoxygen from the materials, thus turning the material oxygen deficient,increasing the oxygen vacancies and electron densities, and leading tohigh dielectric constant and increased loss tangent. Sintering inchromium atmosphere is expected to accommodate a small level of chromiumin the material as a substitution or in the interstitials, thus changingthe material dielectric properties. For example, a sintered sample ofCaCu₃Ti₄O₁₂ in Cr atmosphere has yielded higher dielectric constant andlower loss tangent of 0.033 as compared to the CaCu₃Ti₄O₁₂ sintered inair. This decrease in loss tangent is believed to be the result ofchromium doping. In one embodiment, the amount of chromium incorporatedis less than about 0.01 mol % of the material. In a particularembodiment, the amount of chromium incorporated in the material bysintering in chromium atmosphere is in ppm levels.

In one experiment, BST materials were subjected to cold isostaticpressing (CIP) and also were sintered in oxygen atmosphere for obtainingbetter dielectric values. Examples include, but not limited to,Ba_(0.55)Sr_(0.4)Ca_(0.05)Cr_(0.01)Ti_(0.99)O₃ sintered in oxygenatmosphere at about 1440° C. for 2 hours that has a dielectric constantvalue greater than about 1300 and the loss tangent value less than about0.001 in the frequency of about 4.95 kHz.

In one embodiment, a dielectric component comprising BST or CCTBSTmaterial systems described in above paragraphs is presented. In oneembodiment, a system comprising a dielectric component that comprisesthe BST or CCTBST materials system is presented.

In one embodiment, the dielectric materials exist in the bulk materialform and are polycrystalline, with grains and grain boundaries.Increased grain boundary conduction in BST or CCTBST material system mayincrease both dielectric constant and loss tangent. For example, ametallic precipitate at the grain boundary creates electrostaticpotential due to the metal and electron interface, thereby increasinggrain boundary conduction and, consequently, the dielectric constant andloss tangent.

In one embodiment, any of the materials described above is doped with abismuth-containing material, such as bismuth oxide. In a furtherembodiment, bismuth exists in a metallic phase in the grain boundariesof the polycrystalline materials used for field-focusing element. In arelated embodiment, bismuth oxide is doped and reduced to becomemetallic bismuth in the grain boundaries of the dielectric material. Inone embodiment, the bismuth oxide is introduced to the grain boundariesby mixing Bi₂O₃ and TiO₂ with the calcined BST powders before formingthe BST materials into the bulk form that is incorporable into acomponent, and sintering.

In one embodiment, less than about 3 mole % of Bi₂O₃.3TiO₂ is presentthe CCT material system. The CCT material system doped with Bi₂O₃.3TiO₂show very good temperature stability up to about 700° C. along withreasonable voltage tunability as will be further demonstrated in theexamples and figures below. Temperature stable dielectric materials areadvantageous in preparing devices that work efficiently regardless oftemperature variations. Applications of temperature-stable dielectricmaterials include, but are not limited to, high temperature stabledevices including sensors, multilayer ceramic capacitors, and dielectricabsorbers. For example, the dielectric materials described above may beused as the robust absorption materials of electromagnetic waves inindustries such as aviation so that the airplane is not easily detectedby the radar system.

In one embodiment, less than about 3 mole % of Bi₂O₃.3TiO₂ is presentthe BST material system. In one embodiment, the BST material system hasa metallic bismuth phase in the grain boundaries. It is found that thedielectric constant of the BST material system increases significantlyby having a metallic bismuth phase in the grain boundaries. In someinstances, the increment in dielectric constant value of the BSTmaterial system by disposing metallic bismuth in the grain boundary wasmore than about two orders of magnitude. The BST material system withgrain boundary bismuth precipitation, the material is temperature stableup to about 200° C. while exhibiting an enhanced voltage tunabilityshowing variations in the dielectric constant at low levels of voltagesuch as up to about 5 volts.

The voltage tunable characteristic of a dielectric material system isuseful in many applications such as, but not limited to, varactor diodereplacement, tunable capacitors with low losses, tunable filters, phaseshifters, multiplexers, voltage control oscillators, tunable matchingnetwork for power amplifiers, low noise amplifiers, thermoelectriceffect including power systems, general impedance matching network,wireless communication antennas and inverted F-antenna that is tunedusing a ferroelectric capacitor, phased array antennas made usingdielectric thick films, ferroelectric varactors for capacitive shuntswitching, liquid crystal displays, limiters of electromagnetic wavesand more particularly to RF waves, spatial light modulator,thermodynamically stable substrate type materials for electronicsemiconductor devices, optical switches using ferroelectric liquidcrystal displays, radio frequency phase shift devices or the devicescapable of producing a continuous, reciprocal, differential RF phaseshift with a single control voltage, tunable radio frequency (RF)microelecromechanical system (MEMS) capacitive switches and electricallytunable delay line.

Examples for the BST materials that had grain boundary doping, and thatshow desirable dielectric properties, includeBa_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃ doped with about 1 mole %Bi₂O₃.3TiO₂. This material showed a dielectric constant of about 7668with a dielectric loss of about 0.007 at about 1.4 MHz. Another exampleof a dielectric material with both cation and grain boundary doping isBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O₃ doped with about 1 mole %Bi₂O₃.3TiO₂. This material demonstrates a very high dielectric constantof greater than about 3,470,000 at the frequency of about 100 Hz.However, this material has a high loss tangent value of about 1 that maylimit the application of the material in high power transferapplication.

In one embodiment, a BST material system having an anion doping isfurther doped with grain boundary dopants. In one embodiment, oxygen ispartially replaced by nitrogen and bismuth was disposed in the grainboundaries. An example of a BST material that had both anion doping andgrain boundary doping, and that showed desirable dielectric properties,includes Ba_(0.3)Sr_(0.7)TiO_(2.8)N_(0.13) doped with about 1 mole %Bi₂O₃.3TiO₂. The above-mentioned material showed an extremely highdielectric constant of about 1,793,610 at the frequency of about 100 Hz.However, this material had a loss tangent of about 1. This material canbe used for low power transfer systems. Further, experimenting ondifferent substitution or methods for bringing down the loss tangentvalue may result in a more suitable material to be used in othermultiple applications including high power transfer applications.

In one embodiment, a BST material system doped with cations, anions, andgrain boundary dopants is presented. In one embodiment, titanium ispartially replaced by chromium, oxygen is partially replaced bynitrogen, and metallic bismuth is disposed in the grain boundaries. Oneexample of a material having cation, anion, and grain boundary dopantsin the BST material system isBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.13) with about 1 mole %of Bi₂O₃.3TiO₂. This material showed an extremely high dielectricconstant greater than about 63,000 and dielectric loss tangent of about0.006 at a frequency of about 150 kHz. Therefore, this material is verysuitable in multiple dielectric applications.

In one experiment, BST material system was densified by cold isostaticpressing before sintering. In a further embodiment, the material wasalso doped with the bismuth oxide in the grain boundary and the bismuthoxide was reduced to metallic bismuth by reducing atmosphere treatmentsuch as 5% hydrogen in nitrogen at about 1200° C. for about 12 hours. Inone embodiment, a bismuth doped BST material system is presented. Theexamples include the materials such asBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃+1 mole % Bi₂O₃.3TiO₂ andBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃+1 mole % Bi₂O₃.3TiO₂. Theabove-mentioned materials demonstrate extremely high dielectric constantof greater than about 11,030,000 at a frequency of about 100 Hz.However, the dielectric loss tangent of the materials has a somewhathigh value of about 0.9 at a frequency of about 100 Hz. These materialsmay be useful in applications where a high dielectric constant is ofhigh importance while the high loss tangent values can be accommodatedsuch as in low power transfer applications, for example.

In some applications, it is desirable to employ dielectric materialswhose dielectric properties such as dielectric constant and/or losstangent are stable over a certain temperature range around roomtemperature to accommodate the changes in temperature due to, forexample, environmental or operational changes. In one embodiment, thedielectric materials are beneficial if their dielectric properties aresubstantially stable from about −50° C. to about 150° C. “Substantiallystable” as used herein indicates that the dielectric properties of thematerials do not change more than about 10% of their room temperaturevalues over a given temperature range. In one embodiment, the dielectricmaterials presented herein are having their dielectric propertiessubstantially stable from about −15° C. to about 120° C. In a furtherembodiment, the dielectric materials have dielectric properties that aresubstantially stable from about −20° C. to about 60° C. In oneembodiment, the BST and CCTBST materials presented here are ceramicmaterials stable over a wide temperature range and having dielectricproperties that are stable around room temperatures.

In some applications, it is desirable to employ dielectric materialswhose dielectric properties such as dielectric constant and/or losstangent are stable over a certain voltage range to accommodate theapplications that may have certain variations in voltages. In oneembodiment, the dielectric materials are beneficial if their dielectricproperties are substantially stable up to about 200V. “Substantiallystable” as used herein indicates that the dielectric properties of thematerials do not change more than about 10% over a given voltage range.In one embodiment, the dielectric materials presented herein are havingtheir dielectric properties substantially stable up to about 150V. In afurther embodiment, the dielectric materials have dielectric propertiesthat are substantially stable up to about 100V.

In some applications, it is desirable to employ dielectric materialswhose dielectric properties such as dielectric constant and/or losstangent vary with voltage variations to accommodate the applicationsthat may need variable dielectric properties at varied voltages. Thevariation of dielectric properties may be any function of voltagevariations including directly proportional, inversely proportional tovoltage variation.

EXAMPLES

The following examples illustrate methods, materials and results, inaccordance with specific embodiments, and as such should not beconstrued as imposing limitations upon the claims. All components arecommercially available from common chemical suppliers.

Preparation of Materials:

A general method of preparation followed for the BST, CCT, and CCTBSTmaterial systems identified in different examples are outlined below.However, one skilled in the art would appreciate that small variationsin the starting materials; temperatures, times, and atmospheres ofpreparation, calcination, and sintering; size and shape variations ofthe prepared powders and bulk materials could be accommodated to theexamples presented below.

Preparation of Doped CCT and BST Material Systems

Stoichiometric concentrations of CaCO₃, CuO and TiO₂ were mixed andball-milled in dry conditions and calcined at 1000° C. for 24 hours inair. The calcination temperatures and atmospheres were varied for somematerials to investigate the effect of temperatures and atmospheres.BaCO₃, SrCO₃, Cr₂O₃, Al₂O₃, La₂O₃, ZrO₂ were added in the required molepercents by solid state mixing for doping barium, strontium, chromium,aluminum, lanthanum, and zirconium dopants respectively, wheneverrequired. About 1 mole % of Bi₂O₃.3TiO₂ was added for grain boundarydoping. Urea was used for nitrogen doping in oxygen sites by solid statemixing and calcining Stoichiometric amounts of BaF₂, SrF₂, and/or CaF₂were used as starting materials for including a fluorine dopant in theoxygen site.

The calcined mixture was added with about 2 wt % polyvinyl acetate (PVA)and mixed thoroughly using an agate mortar. The mixture was furthermilled using ball milling in isopropanol medium. The powders werepressed into green pellets using hydraulic pressing with a pressure of 4MPa followed by 6 MPa. For obtaining cold isostatic pressed (CIP)pellets, a CIP machine was used to further densify the hydrostaticallypressed pellets. The pellets were then sintered at 1050° C., 1100° C.,1350° C., or 1440° C. for 2, 12, or 24 hours in air, oxygen, chromium,or nitrogen atmosphere, as required. 5% hydrogen in nitrogen atmospherewas used for reducing bismuth oxide to metallic bismuth duringsintering. The sintered pellets were coated with silver paste for thepurpose of dielectric measurement. The dielectric measurements werecarried out using an Agilent 4294A impedance analyzer and verified usinga Novocontrol Alpha-K impedance analyzer. XRDs of the calcined andsintered samples were verified. While the general method for thepreparation, processing and dielectric value measurements of materialsare outlined above, the examples provided below contain the specificdetails of preparation, processing, measurements, and results of some ofthe selected materials.

Example 1 Ba_(0.55)Sr_(0.4)Ca_(0.05)TiO₃ Processed By CIP

About 13.071 gm of BaCO₃, 9.579 gm of TiO₂, 10.152 gm of Sr(NO₃)₂ and0.6 gm of CaCO₃ were added together and hand mixed using mortar andpestle for 15 minutes. The mixture was added with approximately equalvolume of isopropanol and about 3 times by volume of zirconia grindingmedia and rack-milled for around 6 hours. The homogeneous mixture wastransferred to an alumina crucible and calcined at 1100° C. for 2 hrs.About 2 wt % of PVA was added and mixed to the calcined powder using anagate mortar. Equal volume of isopropanol was added to the resultantmaterial and rack-milled again.

The powder was then pressed into pellets of about 3 gram weight usinghydraulic pressing with a pressure of about 4 MPa. The pellets werevacuum sealed in polyethylene film and cold isostatically pressed withabout 30MPa pressure. The pellets were sintered at 1440° C. for 2 hoursin air. A silver paste coating of a few microns thickness was applied tothe sintered pellets and was dried at 200° C. for 2 hours. Thedielectric constant and loss tangent of the pellet were then measuredusing Agilent 4294A impedance analyzer. Table 5 presents the dielectricmeasurement results of this material.

TABLE 5 Frequency Dielectric constant Loss tangent 100 Hz 3156.7 0.25151 kHz 2491.1 0.1169 10 kHz 2295.2 0.0367 100 kHz 2238.2 0.0144 1 MHz2208.9 0.0069 2.01 MHz 2218.8 0.001 10 MHz 3101.5 0.1617

Example 2 Ba_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂

About 0.079 gm of BaCO₃, 12.790 gm of TiO₂, 1.175 gm of SrCO₃, 3.165 gmof CaCO₃ and 9.554 gm of CuO were added together and hand mixed usingmortar and pestle for 15 minutes. The mixture was added withapproximately equal volume of isopropanol and about 3 times by volume ofzirconia grinding media and rack-milled for around 6 hours. Thehomogeneous mixture was transferred to an alumina crucible and calcinedat 1000° C. for 24 hrs. About 2 wt % of PVA was added and mixed to thecalcined powder using an agate mortar. Equal volume of isopropanol wasadded to the resultant material and rack-milled again.

The powder was then pressed into pellets of about 3 gram weight usinghydraulic pressing with a pressure of about 6 MPa. The pellets weresintered at 1100° C. for 2 hours in air. A silver paste coating of a fewmicrons thickness was applied to the sintered pellets and was dried at200° C. for 2 hours. The dielectric constant and loss tangent of thepellet were then measured using Agilent 4294A impedance analyzer. Table6 presents the dielectric measurement results of this material.

TABLE 6 Frequency Dielectric constant Loss tangent 1 Hz 5345.2 0.069 10kHz 4864.5 0.0634 34 kHz 4672.2 0.0604 100 kHz 4528 0.0794 1 MHz 3638.80.3972 10 MHz 3638.8 2.904

Example 3 Ca₂Cu₂Ti_(3.94)Al_(0.06)O_(11.97)

About 8.497CaCO₃, 6.753 gm of CuO, 13.357 gm of TiO₂ and 0.955 gm ofAl(NO₃)₃.9H₂O were added together and hand mixed using mortar and pestlefor 15 minutes. The mixture was added with approximately equal volume ofisopropanol and about 3 times by volume of zirconia grinding media andrack-milled for around 6 hours. The homogeneous mixture was transferredto an alumina crucible and calcined at 1000° C. for 24 hrs. About 2 wt %of PVA was added and mixed to the calcined powder using an agate mortar.Equal volume of isopropanol was added to the resultant material andrack-milled again.

The powder was then pressed into pellets of about 3 gram weight usinghydraulic pressing with a pressure of about 6 MPa. The pellets weresintered at 1100° C. for 2 hours in air. A silver paste coating of a fewmicrons thickness was applied to the sintered pellets and was dried at200° C. for 2 hours. The dielectric constant and loss tangent of thepellet were then measured using Agilent 4294A impedance analyzer. Table7 presents the dielectric measurement results of this material.

TABLE 7 Frequency Dielectric constant Loss tangent 3.41 kHz 2354.4 0.0213.83 kHz 2344.4 0.0173 10 kHz 2303.1 0.0353 100 kHz 2203.7 0.0612 1 MHz1948.4 0.349 10 MHz 706.7 1.16Temperature and Voltage Dependency of Different Dielectric Materials

FIGS. 2-121 depict the variation of dielectric properties with respectto temperature and voltage of some of the claimed materials as detailedbelow.

FIG. 2 depicts the variation of dielectric constant of0.6CaCu₃Ti_(3.9)4Al_(0.06)O_(11.97)+0.4SrTiO₃ with respect totemperature.

FIG. 3 depicts the variation of loss tangent of0.6CaCu₃Ti_(3.9)4Al_(0.06)O_(11.97)+0.4SrTiO₃ with respect totemperature.

FIG. 4 depicts the variation of dielectric constant of0.6CaCu₃Ti_(3.9)4Al_(0.06)O_(11.97)+0.4SrTiO₃ with respect to voltage.

FIG. 5 depicts the variation of loss tangent of0.6CaCu₃Ti_(3.9)4Al_(0.06)O_(11.97)+0.4SrTiO₃ with respect to voltage.

FIG. 6 depicts the variation of dielectric constant ofCaCu_(2.9)La_(0.067)Ti_(3.94)Al_(0.06)O_(11.97) with respect totemperature.

FIG. 7 depicts the variation of loss tangent ofCaCu_(2.9)La_(0.067)Ti_(3.94)Al_(0.06)O_(11.97) with respect totemperature.

FIG. 8 depicts the variation of dielectric constant ofCaCu_(2.9)La_(0.067)Ti_(3.94)Al_(0.06)O_(11.97) with respect to voltage.

FIG. 9 depicts the variation of loss tangent ofCaCu_(2.9)La_(0.067)Ti_(3.94)Al_(0.06)O_(11.97) with respect to voltage.

FIG. 10 depicts the variation of dielectric constant ofCa₂Cu₂Ti_(3.94)Al_(0.06)O_(11.97) with respect to temperature.

FIG. 11 depicts the variation of loss tangent ofCa₂Cu₂Ti_(3.94)Al_(0.06)O_(11.97) with respect to temperature.

FIG. 12 depicts the variation of dielectric constant ofCa₂Cu₂Ti_(3.94)Al_(0.06)O_(11.97) with respect to voltage.

FIG. 13 depicts the variation of loss tangent ofCa₂Cu₂Ti_(3.94)Al_(0.06)O_(11.97) with respect to voltage.

FIG. 14 depicts the variation of dielectric constant ofCa₂Cu₂Ti_(3.99)Zr_(0.01)O_(11.995) with respect to temperature.

FIG. 15 depicts the variation of loss tangent ofCa₂Cu₂Ti_(3.99)Zr_(0.01)O_(11.995) with respect to temperature.

FIG. 16 depicts the variation of dielectric constant ofCa₂Cu₂Ti_(3.99)Zr_(0.01)O_(11.995) with respect to voltage.

FIG. 17 depicts the variation of loss tangent ofCa₂Cu₂Ti_(3.99)Zr_(0.01)O_(11.995) with respect to voltage.

FIG. 18 depicts the variation of dielectric constant ofCaCu₃Ti_(3.94)Al_(0.06)O_(11.97) with respect to temperature.

FIG. 19 depicts the variation of loss tangent ofCaCu₃Ti_(3.94)Al_(0.06)O_(11.97) with respect to temperature.

FIG. 20 depicts the variation of dielectric constant ofCaCu₃Ti_(3.94)Al_(0.06)O_(11.97) with respect to voltage.

FIG. 21 depicts the variation of loss tangent ofCaCu₃Ti_(3.94)Al_(0.06)O_(11.97) with respect to voltage.

FIG. 22 depicts the variation of dielectric constant of0.6CaCu₃Ti₄O₁₂+0.4SrTiO₃ with respect to temperature.

FIG. 23 depicts the variation of loss tangent of0.6CaCu₃Ti₄O₁₂+0.4SrTiO₃ with respect to temperature.

FIG. 24 depicts the variation of dielectric constant of0.6CaCu₃Ti₄O₁₂+0.4SrTiO₃ with respect to voltage.

FIG. 25 depicts the variation of loss tangent of0.6CaCu₃Ti₄O₁₂+0.4SrTiO₃ with respect to voltage.

FIG. 26 depicts the variation of dielectric constant ofCa₂Cu_(1.9)La_(0.067)Ti₄O₁₂ with respect to temperature.

FIG. 27 depicts the variation of loss tangent ofCa₂Cu_(1.9)La_(0.067)Ti₄O₁₂ with respect to temperature.

FIG. 28 depicts the variation of dielectric constant ofCa₂Cu_(1.9)La_(0.067)Ti₄O₁₂ with respect to voltage.

FIG. 29 depicts the variation of loss tangent ofCa₂Cu_(1.9)La_(0.067)Ti₄O₁₂ with respect to voltage.

FIG. 30 depicts the variation of dielectric constant ofCa₂Cu_(z)Ti_(3.98)Cr_(0.02)O_(11.99) with respect to temperature.

FIG. 31 depicts the variation of loss tangent ofCa₂Cu₂Ti_(3.98)Cr_(0.02)O_(11.99) with respect to temperature.

FIG. 32 depicts the variation of dielectric constant ofCa₂Cu₂Ti_(3.98)Cr_(0.02)O_(11.99) with respect to voltage.

FIG. 33 depicts the variation of loss tangent ofCa₂Cu₂Ti_(3.98)Cr_(0.02)O_(11.99) with respect to voltage.

FIG. 34 depicts the variation of dielectric constant ofCaCu₃Ti_(3.92)Cr_(0.02)Al_(0.06)O_(11.96) with respect to temperature.

FIG. 35 depicts the variation of loss tangent ofCaCu₃Ti_(3.92)Cr_(0.02)Al_(0.06)O_(11.96) with respect to temperature.

FIG. 36 depicts the variation of dielectric constant ofCaCu₃Ti_(3.92)Cr_(0.02)Al_(0.06)O_(11.96) with respect to voltage.

FIG. 37 depicts the variation of loss tangent ofCaCu₃Ti_(3.92)Cr_(0.02)Al_(0.06)O_(11.96) with respect to voltage.

FIG. 38 depicts the variation of dielectric constant ofCaCu₃Ti_(3.98)Cr_(0.02)O_(11.99) with respect to temperature.

FIG. 39 depicts the variation of loss tangent ofCaCu₃Ti_(3.98)Cr_(0.02)O_(11.99) with respect to temperature.

FIG. 40 depicts the variation of dielectric constant ofCaCu₃Ti_(3.98)Cr_(0.02)O_(11.99) with respect to voltage.

FIG. 41 depicts the variation of loss tangent ofCaCu₃Ti_(3.98)Cr_(0.02)O_(11.99) with respect to voltage.

FIG. 42 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 43 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 44 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 45 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 46 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 47 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 48 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 49 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mole % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 50 depicts the variation of dielectric constant with respect totemperature of Ba_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃ doped with 1 mole% Bi₂O₃.3TiO₂ prepared by sintering in 5% hydrogen and 95% nitrogenatmosphere at 1200° C.

FIG. 51 depicts the variation of loss tangent with respect totemperature of Ba_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃ doped with 1 mole% Bi₂O₃.3TiO₂ prepared by sintering in 5% hydrogen and 95% nitrogenatmosphere at 1200° C.

FIG. 52 depicts the variation of dielectric constant with respect tovoltage of Ba_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃ doped with 1 mole %Bi₂O₃.3TiO₂ prepared by sintering in 5% hydrogen and 95% nitrogenatmosphere at 1200° C.

FIG. 53 depicts the variation of loss tangent with respect to voltage ofBa_(0.3)Sr_(0.7)Cr_(0.002)Ti_(0.998)O₃ doped with 1 mole % Bi₂O₃.3TiO₂prepared by sintering in 5% hydrogen and 95% nitrogen atmosphere at1200° C.

FIG. 54 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to temperature.

FIG. 55 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to temperature.

FIG. 56 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to voltage.

FIG. 57 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to voltage.

FIG. 58 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 59 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 60 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 61 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 62 depicts the variation of dielectric constant ofBa_(0.55)Sr_(0.4)Ca_(0.05)Cr_(0.01)Ti_(0.99)O₃ with respect totemperature.

FIG. 63 depicts the variation of loss tangent ofBa_(0.55)Sr_(0.4)Ca_(0.05)Cr_(0.01)Ti_(0.99)O₃ with respect totemperature.

FIG. 64 depicts the variation of dielectric constant ofBa_(0.55)Sr_(0.4)Ca_(0.05)Cr_(0.01)Ti_(0.99)O₃ with respect to voltage.

FIG. 65 depicts the variation of loss tangent ofBa_(0.55)Sr_(0.4)Ca_(0.05)Cr_(0.01)Ti_(0.99)O₃ with respect to voltage.

FIG. 66 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ with respect to temperature.

FIG. 67 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ with respect to temperature.

FIG. 68 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ with respect to voltage.

FIG. 69 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ with respect to voltage.

FIG. 70 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 71 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to temperature.

FIG. 72 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 73 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.01)Ti_(0.99)O₃ doped with 1 mol % Bi₂O₃.3TiO₂,with respect to voltage.

FIG. 74 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ with respect to temperature.

FIG. 75 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ with respect to temperature.

FIG. 76 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ with respect to voltage.

FIG. 77 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O₃ with respect to voltage.

FIG. 78 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.002)Ti_(0.998)O₃ with respect to temperature.

FIG. 79 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.002)Ti_(0.998)O₃ with respect to temperature.

FIG. 80 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.002)Ti_(0.998)O₃ with respect to voltage.

FIG. 81 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.002)Ti_(0.998)O₃ with respect to voltage.

FIG. 82 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect totemperature.

FIG. 83 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect totemperature.

FIG. 84 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect tovoltage.

FIG. 85 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect tovoltage.

FIG. 86 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect totemperature.

FIG. 87 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect totemperature.

FIG. 88 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect tovoltage.

FIG. 89 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) with respect tovoltage.

FIG. 90 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) doped with 1 mol %Bi₂O₃.3TiO₂, with respect to temperature.

FIG. 91 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) doped with 1 mol %Bi₂O₃.3TiO₂, with respect to temperature.

FIG. 92 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) doped with 1 mol %Bi₂O₃.3TiO₂, with respect to voltage.

FIG. 93 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)Cr_(0.005)Ti_(0.995)O_(2.8)N_(0.2) doped with 1 mol %Bi₂O₃.3TiO₂, with respect to voltage.

FIG. 94 depicts the variation of dielectric constant with respect totemperature of Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂.

FIG. 95 depicts the variation of loss tangent with respect totemperature of Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂.

FIG. 96 depicts the variation of dielectric constant with respect tovoltage of Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂.

FIG. 97 depicts the variation of loss tangent with respect to voltage ofBa_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂.

FIG. 98 depicts the variation of dielectric constant with respect totemperature of Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂ anddoped with 1 mol % Bi₂O₃.3TiO₂.

FIG. 99 depicts the variation of loss tangent with respect totemperature of Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂ anddoped with 1 mol % Bi₂O₃.3TiO₂.

FIG. 100 depicts the variation of dielectric constant with respect tovoltage of Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂ anddoped with 1 mol % Bi₂O₃.3TiO₂.

FIG. 101 depicts the variation of loss tangent with respect to voltageof Ba_(0.4)Sr_(0.6)TiO₃ prepared by using BaF₂ and SrF₂ and doped with 1mol % Bi₂O₃.3TiO₂.

FIG. 102 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) with respect to temperature.

FIG. 103 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) with respect to temperature.

FIG. 104 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) with respect to voltage.

FIG. 105 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) with respect to voltage.

FIG. 106 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) with respect to temperature.

FIG. 107 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) with respect to temperature.

FIG. 108 depicts the variation of dielectric constant ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) with respect to voltage.

FIG. 109 depicts the variation of loss tangent ofBa_(0.4)Sr_(0.6)TiO_(2.8)N_(0.2) with respect to voltage.

FIG. 110 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to temperature.

FIG. 111 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to temperature.

FIG. 112 depicts the variation of dielectric constant ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to voltage.

FIG. 113 depicts the variation of loss tangent ofBa_(0.3)Sr_(0.7)TiO_(2.8)N_(0.2) doped with 1 mol % Bi₂O₃.3TiO₂, withrespect to voltage.

FIG. 114 depicts the variation of dielectric constant ofBa_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂ with respect to temperature.

FIG. 115 depicts the variation of loss tangent ofBa_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂ with respect to temperature.

FIG. 116 depicts the variation of dielectric constant ofBa_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂ with respect to voltage.

FIG. 117 depicts the variation of loss tangent ofBa_(0.01)Sr_(0.2)Ca_(0.79)Cu₃Ti₄O₁₂ with respect to voltage.

FIG. 118 depicts the variation of dielectric constant ofCaCu₃Ti_(3.99)Zr_(0.01)O_(11.995) with respect to temperature.

FIG. 119 depicts the variation of loss tangent ofCaCu₃Ti_(3.99)Zr_(0.01)O_(11.995) with respect to temperature.

FIG. 120 depicts the variation of dielectric constant ofCaCu₃Ti_(3.99)Zr_(0.01)O_(11.995) with respect to voltage.

FIG. 121 depicts the variation of loss tangent ofCaCu₃Ti_(3.99)Zr_(0.01)O_(11.995) with respect to voltage.

While the exceptions may not be ruled out, general observations aboutthe temperature and voltage dependency of the above mentioned materialsare as described below. In general, materials based on CCT materialsystem encompassing FIG. 1-41 and FIG. 118-121 show uniform changes withrespect to increasing temperature. It is observed that the loss tangentof the material increases with increasing temperature and the dielectricconstant generally increases with a very low coefficient of temperature.This material system shows voltage tunability of dielectric constantwith high levels of voltage up to about 200 V, while loss tangent, asdepicted, is nearly constant with increasing voltage at all thefrequencies.

In general, BST with metallic bismuth precipitate in the grain boundaryencompassing FIGS. 41-61, 71-74, 90-94, 98-101, and 110-113 show uniformdielectric properties with increasing temperature up to about 200° C.The dielectric constant of this material increases with temperature witha very low coefficient of temperature. Further, BST with metallicbismuth precipitate in the grain boundary shows sharp voltage tunabilitywith low levels of voltage, such as for example, up to about 5 V forsome materials and up to about 40 V for some other materials.

In general, the Ba_(0.55)Sr_(0.4)Ca_(0.05)Cr_(0.01)Ti_(0.99)O₃ systemhas a phase transition below room temperature and, therefore, thedielectric constant shows a decreasing trend from room temperature to200° C. with increasing temperature as can be seen from FIG. 62. Thedielectric constant of this material is constant with voltage levels upto 200 V as shown in FIG. 64. Similarly, from the FIGS. 66-69, 74-89,94-97, and 102-109, it can be seen that the dielectric constant of BSTmaterial system shows a decreasing trend from room temperature to 200°C. and shows voltage tunability with high levels of voltage, forexample, up to about 200 V. The loss tangent of this system is nearlyconstant with increasing voltage at almost all the frequencies.

FIG. 114-117 shows up the temperature and voltage dependency of(Ba,Sr,Ca)Cu₃Ti₄O₁₂ system. The dielectric constant of this materialincreases with a very low coefficient of temperature. The loss tangentshows a similar trend with a very minute change the magnitude withincreasing temperature. The dielectric constant of this system showssome voltage tunability with high levels of voltage up to about 200 V.The loss tangent, as depicted, is nearly constant with increasingvoltage at almost all frequencies.

While only certain features of the invention have been illustrated anddescribed herein, many modifications and changes will occur to thoseskilled in the art. It is, therefore, to be understood that the appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit of the invention.

The invention claimed is:
 1. A material comprising:α[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof, and0≦x≦0.1, 0≦y≦1, 0≦z≦1, 0≦p≦0.1, 0≦q≦0.1, 0≦δ≦0.05, 0≦r≦1, and 0.5≦α≦1,with a proviso that when z=α=1, and p=q=0, x>0 and y>0; when x=y=0 andz=α=1, p and q are greater than zero; and when x=y=z=0, p and q are notsimultaneously zero.
 2. The material of claim 1, comprisingCaCu_(2.9)La_(0.067)Ti_(3.94)A1 _(0.06)O_(12-δ).
 3. The material ofclaim 1, comprising CaCU_(2.9)La_(0.067)Ti_(3.99)Zr_(0.01)O_(12-δ). 4.The material of claim 1, comprisingCaCu_(2.9)La_(0.067)Ti_(3.98)Cr_(0.02)O_(12-δ).
 5. The material of claim1, comprising CaCu₃Ti_(3.92)Cr_(0.02)Al_(0.06)O_(12-δ).
 6. The materialof claim 1, comprising Ca₂Cu₂Ti_(3.94)Al_(0.06)O_(12-δ).
 7. The materialof claim 1, comprising Ca₂Cu₂Ti_(3.98)Cr_(0.02)O_(12-δ).
 8. The materialof claim 1, comprising Ca₂Cu_(1.9)La_(0.067)Ti₄O₁₂.
 9. The material ofclaim 1, comprising Ca₂Cu₂Ti_(3.99)Zr_(0.01)O₁₂.
 10. The material ofclaim 1, comprising Ba_(0.01)Sr_(0.1)Ca_(0.89)Cu₃Ti₄O₁₂.
 11. Thematerial of claim 1, comprising0.6[CaCu₃Ti_(3.94)Al_(0.06)O_(12-δ)]+0.4[SrTiO₃].
 12. The material ofclaim 1, comprising 0.6[CaCu₃Ti_(3.98)Cr_(0.02)O_(12-δ)]+0.4[SrTiO₃].13. A dielectric component comprising: a material comprisingα[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof, and0≦x≦0.1, 0≦y≦1, 0≦z≦1, 0≦p≦0.1, 0≦q≦0.1, 0≦δ≦0.05, 0≦r≦1, and 0.5≦α≦1,with a proviso that when z=α=1, and p=q=0, x>0 and y>0; when x=y=0 andz=α=1, p and q are greater than zero; and when x=y=z=0, p and q are notsimultaneously zero.
 14. A system comprising: a dielectric componentcomprising a material comprising α[Ca_(1-x-y)Ba_(x)Sr_(y)(Ca_(1-z)Cu_(z))Cu_(2-p)La_(2p/3)Ti_(4-q)M_(q)O_(12-δ)]+(1−α)[Ba_(r)Sr_(1-r)TiO₃],wherein M is aluminum, chromium, zirconium, or combinations thereof, and0≦x≦0.1, 0≦y≦1, 0≦z≦1, 0≦p≦0.1, 0≦q≦0.1, 0≦δ≦0.05, 0≦r≦1, and 0.5≦α≦1,with a proviso that when z=α=1, and p=q=0, x>0 and y>0; when x=y=0 andz=α=1, p and q are greater than zero; and when x=y=z=0, p and q are notsimultaneously zero.